As the prospect of some sort of state-supervised receivership looms larger for Detroit, politicians who exploit racial division for fun and profit are fond of pointing out that all four of the Michigan cities currently under such supervision are predominantly African American.

This is a little like observing that all Victoria's Secret models have manicured fingernails. True enough, but flawless nails aren't what landed them in a lingerie catalog.

It's the same with the four cities in which Gov. Rick Snyder or his predecessor have installed emergency managers. Yes, all of them have black electoral majorities. And in each of the four, most of the elected leaders displaced by an appointed emergency manager were African American.

But Benton Harbor, Ecorse, Flint and Pontiac have something much more important in common: They're all shrinking -- hemorrhaging taxpayers, homeowners, employers at an alarming rate.

And in each case, African Americans are rushing for the exits just as fast, and in some cases faster, than their white, Latino and Asian neighbors.

Diverse diaspora

The numbers in the accompanying chart tell the story succinctly: In the decade between the U.S. census counts in 2000 and 2010, Benton Harbor and Pontiac both lost more 10% of their residents. Ecorse and Flint lost more than 15%, and Detroit, the city currently atop the state treasurer's critical list, lost 25%.

In four of those five cities, the pace of the African-American exodus has matched that of other residents. In the case of Benton Harbor, African-American residents have actually been abandoning ship faster than their white neighbors: The city's overall population shrunk by 10.2% from 2000-10, but the African-American population plummeted by 13.3%.

There are a lot of ways to describe this phenomenon, but white flight seems less and less useful. In Detroit, in particular, it is increasingly a matter of African Americans with educational credentials, cars and employment options leaving behind African Americans with none of those advantages.

Homesteaders needed?

The cities in which the state has had to appoint emergency managers are those in which the costs of municipal infrastructures that once served much larger populations are now borne by thousands, or even hundreds of thousands, fewer wage-earning, tax-paying residents.

The bad news for such cities is that the changes and dislocations required to bring revenues and expenses back into balance are so wrenching that popularly elected leaders are loath to make them; the worse news is that even those dramatic reductions may be insufficient to make those cities sustainable in the face of continuing population losses.

Reversing the population trends that have reduced Michigan's most troubled cities to their current dire straits may require interventions beyond the capacity of either elected leaders or appointed emergency managers, such as reducing barriers to legal immigration for foreigners willing to locate in cities or neighborhoods with excess capacity.

In the future, as in the present, the race or national origin of such intrepid urban homesteaders will matter far less than their critical mass.